HOUSTON (Reuters) - U.S. oil companies were closely watching a large tropical disturbance in the southern Gulf of Mexico, but were not changing operations despite the system's 70 percent chance of developing into a tropical cyclone over the next 48 hours, according the U.S. National Hurricane Center.
Leading oil producer in the U.S.-regulated Gulf of Mexico Shell Oil Co, the U.S. arm of Royal Dutch Shell, said it was monitoring the storm on Sunday.
"We're keeping an eye on it, but no changes in operations yet," said Shell spokesman Ray Fisher on Sunday.
The system does not yet have a closed circulation needed to classify it as a tropical storm or hurricane, but was producing winds near gale force or about 38 miles per hour (61 kilometers per hour), or about half the strength of winds generated in the weakest hurricane.
The National Hurricane Center as well as academic and private weather forecasters are expecting a below-average Atlantic Ocean hurricane season for the United States this year. The season began on June 1 and lasts through Nov. 30.
Some forecasters have warned that the best chance for a tropical storm to develop in the oil production areas off the U.S. Coast could come early in the hurricane season. A strong El Nino is expected to form in the eastern Pacific later this summer and is expected to send high winds across the southern United States, disrupting tropical storm development.
The Gulf of Mexico produces 17 percent of U.S. crude oil production and 5 percent of dry national gas output, according to the U.S. Energy Information Administration.
Gulf Coast states of Texas, Louisiana and Mississippi are also home to more than 45 percent of the nation's crude oil refining capacity, according to the EIA.
(Reporting by Erwin Seba; Editing by Bernard Orr)